Subject: Re: [WIP] Effective storage of duplicates in B-tree index.
To: Alexander Korotkov <a.korotkov@postgrespro.ru>, Robert Haas
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CC: Anastasia Lubennikova <a.lubennikova@postgrespro.ru>, David Steele
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From: Jim Nasby <Jim.Nasby@BlueTreble.com>
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Date: Thu, 24 Mar 2016 19:22:49 -0500
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On 3/24/16 10:21 AM, Alexander Korotkov wrote:
> 1) It's a great feature many users dream about.

Doesn't matter if it starts eating their data...

> 2) Patch is not very big.
> 3) Patch doesn't introduce significant infrastructural changes.  It just
> change some well-isolated placed.

It doesn't really matter how big the patch is, it's a question of "What 
did the patch fail to consider?". With something as complicated as the 
btree code, there's ample opportunities for missing things. (And FWIW, 
I'd argue that a 51kB patch is certainly not small, and a patch that is 
doing things in critical sections isn't terribly isolated).

I do think this will be a great addition, but it's just too late to be 
adding this to 9.6.

(BTW, I'm getting bounces from a.lebedev@postgrespro.ru, as well as 
postmaster@. I emailed info@postgrespro.ru about this but never heard back.)
-- 
Jim Nasby, Data Architect, Blue Treble Consulting, Austin TX
Experts in Analytics, Data Architecture and PostgreSQL
Data in Trouble? Get it in Treble! http://BlueTreble.com


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